1. Field of the Invention
The present invention relates to a control input device, and in particular, it relates to a control input device having the function of generating vibration in response to the operation of an operator.
2. Description of the Related Art
Intuitive touch panels have recently been used as input devices for car-mounted navigation systems. In this type of car-mounted navigation systems, the user can control the navigation system by touching a screen (touch panel) on which a map is displayed. The operator can also control an audio-video (AV) system by touching the screen (touch panel) on which an AV control screen is displayed. For example, the user can perform operations such as playback, stop, and volume control by touching the control button on the screen on which a CD-player control screen is displayed.
The operator can determine whether or not he/she has touched the control button on the touch panel by the change in the color of the operation button or by beeper.
However, the operator has to actually see or hear the information. Accordingly, when the operator cannot look at the control screen carefully or when background sound is loud, the operator sometimes cannot confirm that he/she has touched the button.
For this problem, Japanese Unexamined Patent Application Publication No. 8-221173 (Patent Document 1) discloses an input device that provides tactile feedback by specified vibration to the finger when an operator pushes a control button on the touch panel, thereby allowing the operator to recognize that he/she has touched the control button.
However, the technique described in Patent Document 1 merely informs the operator of the fact that the switch of the touch panel is pushed by providing a specified vibration to the operator when the finger of the operator has touched the switch. At the time of playing back music by an audio system such as a CD player, when the operator performs an operation to speed up the playback action (e.g., FWD (fast-forward) key operation), the operator cannot recognize the degree of forwarding of the playback object even when he/she can recognize that the key has been pressed by the vibration. In sum, the operator cannot recognize the changes of the content of the object (music in this case).
Conventional systems have generated vibration on the touch panel when the operator continues to press a FWD key while listening to music played by a CD player, so that a “long key press” is confirmed. When the music being played is changed during the FWD operation, the title of the music is displayed on the display screen. The operator can thus recognize that the music has been changed by viewing the title displayed on the display screen, and when the music is changed to the desired music, the operator releases the FWD key, and selects the desired music.
With such conventional audio systems, the operator can recognize the information after the long key press is confirmed, and then the next music is started only when the operator looks at the display screen. This presents no problem as long as the audio system is not for vehicles. However, when the system is for vehicles and the operator is driving a car, the operator cannot look at the display screen for safety reasons. This therefore poses the problem of determining when the music has been changed to the desired music after a long key press.